Reactive extraction of lactic acid using environmentally benign green solvents and a synergistic mixture of extractants

Abstract

An environment-friendly reactive extraction method as a novel phase separation technique was postulated to extract lactic acid (LA) from aqueous solution by means of environmentally benign green solvents along with the synergistic mixture of extractants. Reactive extraction of LA has been carried by using synergistic mixture of extractants (trioctylamine (TOA), Aliquat336, and tridodecylamine (TDDA)), organic solvents, and non-toxic and biocompatible green solvents. From the different LA reactive extraction systems investigated, the system having sunflower oil, synergist extractant (TOA and Aliquat336) and Butan-2-ol were found to be the most favourable system. The LA distribution coefficient (KD=27.75±0.22) and extraction efficiency (η=97.17±0.54%) were obtained by a system consisting of LA concentration (0.05 [M]), TOA (15%, v/v), Aliquat336 (15%, v/v), solvent ratio (2.5, v/v), phase ratio (1:1, v/v), agitation speed (100 rpm), and stirring time (120 min). The main driving force for this research work on the LA reactive extraction from aqueous solution was to develop a suitable combination of extractants, organic solvents and natural solvents which possesses high affinity towards LA and also has less toxicity towards LA producing microbes.